Portable electronic device

ABSTRACT

Portable electronic devices are provided. A device may include cover glass with a light mask. The light mask may be microperforated to allow light to pass through the light mask. The microperforations may allow light to pass through the light mask. The devices may include sensors and light emitters that receive and transmit light through the microperforations. The devices may include a variable cantilever spring as part of a button assembly. The spring may be flattened against itself without exceeding its elastic limit. The devices may include display modules. The display module may include structures that block light from leaking out of the module. The structures may include opaque tapes, opaque enclosures for the display module, and other suitable structures.

BACKGROUND

This relates generally to electronic devices and, more particularly, toportable electronic devices.

Electronic devices such as portable electronic devices are becomingincreasingly popular. Examples of portable devices include handheldcomputers, cellular telephones, media players, and hybrid devices thatinclude the functionality of multiple devices of this type. Popularportable electronic devices that are somewhat larger than traditionalhandheld electronic devices include laptop computers and tabletcomputers.

An electronic device may include one or more sensors. The sensors may beused to sense information about the environment around the electronicdevice such an ambient light level and the proximity of nearby objects.The electronic device may include one or more apertures that passradiation between the sensors and the external environment. Theapertures may not be aesthetically pleasing and may divert attentionaway from other aesthetically pleasing features of the electronicdevice. It would therefore be desirable to provide electronic devicesthat have improved sensor apertures.

An electronic device may include a housing and a display module mountedin the housing. The display module may emit light through a displayopening in the housing. With conventional display modules, light mayalso escape into the housing from the sides and rear of the displaymodule. The light that escapes into the housing can then escape throughcracks or joints in the housing which is aesthetically undesirable. Itwould therefore be desirable to provide display modules for electronicdevices that minimize light leakage.

Electronic devices may sometimes include a compression spring as part ofa button mechanism. Conventional button springs can become deformed andnon-functional if they are fully compressed. It would therefore bedesirable to provide springs for button mechanisms in an electronicdevice that can be more fully compressed without deforming.

SUMMARY

Portable electronic devices are provided. The electronic devices may behybrid devices that combine the functionality of multiple devices. Anexample of a hybrid electronic device is a cellular telephone thatincludes media player functionality.

An electronic device may include a display and a transparent cover thatcovers the display. The transparent cover may be formed from cover glassand may extend beyond the borders of the display and, if desired, maycover a majority of one or more sides of the electronic device. Forexample, the cover glass may extend almost entirely across the frontface of the electronic device. With one suitable arrangement, theelectronic device may include a mask behind or in front of portions ofthe cover glass to obscure internal components in the electronic devicefrom view. Generally, the mask need not extend across the display.However, if desired, the mask may overlap the edges of the display. Thecover glass and mask may have portions defining holes. As an example,the holes may include a hole for a button mechanism (e.g., a menu buttonhole) and a hole for a speaker (e.g., a port for transmitting soundthrough the cover glass).

A mask for cover glass in an electronic device may includemicroperforations. The microperforations may allow light and otherradiation to pass through the mask and cover glass. With this type ofarrangement, the electronic device may include sensors underneath thecover glass that can transmit and receive radiation through the coverglass. The microperforated mask may allow radiation to pass through themask while simultaneously obscuring the sensors from a user's view. Ingeneral, the electronic device may include any desired type of sensorsuch as a proximity sensor, an ambient light sensor, an orientationsensor, etc. With one suitable arrangement, the mask may be formed froma relatively thin layer of deposited material and, as an example, themicroperforations may be formed using a laser to selectively etch awayportions of the mask.

An electronic device may include a display with structures that reducelight leakage from the display. The display, which is sometimes referredto as a display module, may include a plurality of layers held togetherin a chassis. As an example, the display may include structures thatreduce light leakage from the display such as one or more strips ofopaque tape. Strips of opaque tape may be applied to the exteriorsurface of the display module (e.g., to the exterior surface of achassis for the display) to reduce light leakage from the display (e.g.,to reduce the amount of light that escapes into the interior of theelectronic device). If desired, strips of opaque tape may be placed inthe interior of the display module (e.g., applied to an interior surfaceof the chassis) to reduce light leakage from the display.

An electronic device may include one or more compression springs. Thecompression springs may be a part of a button mechanism in theelectronic device, as an example. With one suitable arrangement, acompression spring may be formed with a curved cantilever shape so thatthe spring does not plastically deform even if the spring is completelycompressed. With another suitable arrangement, a compression spring maybe formed with a variable cantilever shape and may incorporate aself-strengthening tip portion that increases the uncompressed height ofthe spring following a complete compression of the spring.

Further features of the invention, its nature and various advantageswill be more apparent from the accompanying drawings and the followingdetailed description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an illustrative portable electronicdevice in accordance with an embodiment of the present invention.

FIG. 2 is a schematic diagram of an illustrative portable electronicdevice in accordance with an embodiment of the present invention.

FIG. 3 is a cross-sectional side view of a conventional sensor mountedbeneath a cover glass.

FIG. 4 is a cross-sectional side view of an illustrative cover glass ina portable electronic device that may have a light mask showing how thelight mask may be perforated to allow light to pass through portions ofthe light mask in accordance with an embodiment of the presentinvention.

FIG. 5 is a cross-sectional side view of an illustrative sensor andcover glass with a light mask in a portable electronic device that showshow the light mask may be perforated to allow light to pass through thecover glass to the sensor in accordance with an embodiment of thepresent invention.

FIG. 6 is a front view of an illustrative cover glass with a light maskthat may have microperforations to allow light to pass through the coverglass to one or more sensors that may be mounted beneath the cover glassin accordance with an embodiment of the present invention.

FIG. 7 is a front view of an illustrative light mask that may beperforated to allow light to pass through the light mask in accordancewith an embodiment of the present invention.

FIG. 8 is a rear view of an illustrative display module that may includestructures to reduce light leakage from the display module in accordancewith an embodiment of the present invention.

FIG. 9 is a cross-sectional end view of an illustrative display modulethat may include multiple layers and a chassis that holds the layerstogether in accordance with an embodiment of the present invention.

FIG. 10 is a cross-sectional side view of a glass panel layer that maybe part of the illustrative display module of FIG. 9 in accordance withan embodiment of the present invention.

FIG. 11 is a cross-sectional side view of an illustrative display modulethat may be mounted to a mounting structure in an electronic device withdouble-sided tape in accordance with an embodiment of the presentinvention.

FIG. 12 is a side view of a conventional display module with clear tapethat allows light to escape from the display module.

FIG. 13 is a rear view of an illustrative display module with opaquetape that helps to hold the layers of the display module together andthat blocks errant light to prevent the light from escaping from thedisplay module in accordance with an embodiment of the presentinvention.

FIG. 14 is a perspective view of an illustrative compression spring thatmay be a part of a button mechanism in an electronic device inaccordance with an embodiment of the present invention.

FIG. 15 is a side view of the illustrative compression spring of FIG. 14that shows various dimensions of the compression spring in accordancewith an embodiment of the present invention.

FIG. 16 is a bottom view of the illustrative compression spring of FIG.14 showing a portion of the compression spring that may be used as anattachment point for mounting the compression spring in the electronicdevice in accordance with an embodiment of the present invention.

FIG. 17 is a top view of the illustrative compression spring of FIG. 14that shows various dimensions of the compression spring in accordancewith an embodiment of the present invention.

FIG. 18 is a cross-sectional side view of the illustrative compressionspring of FIG. 14 mounted in an illustrative electronic device inaccordance with an embodiment of the present invention.

FIG. 19 is a cross-sectional side view of an illustrative electronicdevice with a button mechanism which includes a pair of compressionsprings in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION

The present invention relates to electronic devices and components inelectronic devices. The electronic devices may be portable electronicdevices such as laptop computers or small portable computers of the typethat are sometimes referred to as ultraportables. Portable electronicdevices may also be somewhat smaller devices. Examples of smallerportable electronic devices include wrist-watch devices, pendantdevices, headphone and earpiece devices, and other wearable andminiature devices.

With one suitable arrangement, the portable electronic devices may bewireless electronic devices. The wireless electronic devices may be, forexample, handheld wireless devices such as cellular telephones, mediaplayers with wireless communications capabilities, handheld computers(also sometimes called personal digital assistants), global positioningsystem (GPS) devices, and handheld gaming devices. The wirelesselectronic devices may also be hybrid devices that combine thefunctionality of multiple conventional devices. Examples of hybridportable electronic devices include a cellular telephone that includesmedia player functionality, a gaming device that includes a wirelesscommunications capability, a cellular telephone that includes game andemail functions, and a portable device that receives email, supportsmobile telephone calls, has media player functionality, and supports webbrowsing. These are merely illustrative examples.

An illustrative electronic device in accordance with an embodiment ofthe present invention is shown in FIG. 1. User device 10 may be anysuitable electronic device such as a portable or handheld electronicdevice. Device 10 of FIG. 1 may be, for example, a handheld electronicdevice that supports 2G and/or 3G cellular telephone and data functions,global positioning system capabilities or other satellite navigationcapabilities, and local wireless communications capabilities (e.g., IEEE802.11 and Bluetooth®) and that supports handheld computing devicefunctions such as internet browsing, email and calendar functions,games, media player functionality, etc.

Device 10 may have housing 12 and display 16. Housing 12, which issometimes referred to as a case, may be formed from any suitablematerial including, plastic, glass, ceramics, metal, or other suitablematerials, or a combination of these and other materials.

Display 16 may be a liquid crystal display (LCD), a thin film transistorliquid crystal display (TFT-LCD), an organic light-emitting diode (OLED)display, or any other suitable display. The outermost surface of display16 may be formed from one or more plastic or glass layers. If desired,touch screen functionality may be integrated into display 16 or may beprovided using a separate touch pad device. With one suitablearrangement, display 16 may include structures that reduce light leakagefrom display 16 (e.g., structures that help to prevent light fromescaping from display 16 to the interior of device 10).

Display screen 16 (e.g., a touch-screen) is merely one example of aninput-output device that may be used with electronic device 10. Ifdesired, electronic device 10 may have other input-output devices. Forexample, electronic device 10 may have user input control devices suchas button 19, and input-output components such as port 20 and one ormore input-output jacks (e.g., for audio and/or video). Button 19 maybe, for example, a menu button. Port 20 may contain a 30-pin data andpower connector (as an example). Openings 22 and 24 may, if desired,form speaker and microphone ports. Speaker port 22 may be used whenoperating device 10 in speakerphone mode. Opening 23 may also form aspeaker port. For example, speaker port 23 may serve as a telephonereceiver that is placed adjacent to a user's ear during operation. Inthe example of FIG. 1, display screen 16 is shown as being mounted onthe front face of handheld electronic device 10, but display screen 16may, if desired, be mounted on the rear face of handheld electronicdevice 10, on a side of device 10, on a flip-up portion of device 10that is attached to a main body portion of device 10 by a hinge (forexample), or using any other suitable mounting arrangement.

If desired, a button mechanism in device 10 such as button 19 mayinclude a compression spring. The spring may be, as one example, avariable cantilever spring that can be fully compressed withoutpermanently deforming (e.g., without undergoing plastic deformation).

A user of electronic device 10 may supply input commands using userinput interface devices such as button 19 and touch screen 16. Suitableuser input interface devices for electronic device 10 include buttons(e.g., alphanumeric keys, power on-off, power-on, power-off, and otherspecialized buttons, etc.), a touch pad, pointing stick, or other cursorcontrol device, a microphone for supplying voice commands, or any othersuitable interface for controlling device 10. Buttons such as button 19and other user input interface devices may be formed on any suitableportion of device 10.

If desired, some or all of the input commands for device 10 may bereceived using accessories. This type of arrangement may help to reducethe size of the device 10 by reducing or even eliminating the number ofcontrol interfaces (e.g., buttons, sliders, etc.) located on the device10. With one suitable arrangement, the device 10 may connect with aheadset through a connector such as connector 20 or an audio connector(e.g., a tip, ring, and sleeve female audio connector) and may receivecontrol commands such as play, pause, stop, fast forward, skip forward,rewind, skip back, volume up, volume down, mute, and other controlcommands from the headset. In this arrangement, a headset may includespeakers and a control unit that generates command signals that can beinterpreted by the device 10. If desired, device 10 can be controlledremotely (e.g., using an infrared remote control, a radio-frequencyremote control such as a Bluetooth® remote control, etc.).

Device 10 may include cover 54. As shown in FIG. 1, cover 54 may extendover a majority of the front surface of device 10. Cover 54 may beformed from transparent glass or other suitable materials. Cover 54 maysurround display 16 or may cover and surround display 16, if desired. Asone example, cover 54 may be opaque and may obscure the internalcomponents (except for display 16) mounted inside device 10. If desired,cover 54 may be somewhat or completely transparent so that a user canview the internal components mounted inside device 10. With one suitablearrangement, cover 54 may be formed from a transparent member such asglass coated on at least one side with an opaque material such as paintor ink. For example, cover 54 may be formed from a sheet of glass thatcovers the front surface of device 10 and from a layer of black paint onthe underside of the sheet of glass. If desired, cover 54 (e.g., a sheetof glass) may extend over display 16 and the periphery of display 16while the layer of black paint may extend over the periphery of display16 but not over display 16. In general, cover 54 may include glass andone or more layers of paint or other structure in any suitable shade andpattern or combination thereof. Cover 54 may sometimes be referred to ascover glass. With one suitable arrangement, display 16 may have anactive image area (e.g., the outlined portion of display 16 in FIG. 1)and an inactive peripheral region (e.g., the regions on the front faceof device 10 beyond the outline portion of display 16 in FIG. 1). As oneexample, cover 54 may include an opaque layer that covers the inactiveperipheral region of display 16. If desired, cover 54 and display 16 maybe integrated together (e.g., cover 54 may be incorporated into display16).

Device 10 may contain sensors for monitoring the environment arounddevice 10. For example, device 10 may include sensors such as acousticsensors, accelerometers, thermometers, altimeters and/or barometers,proximity sensors, ambient light sensors, etc. If desired, device 10 mayinclude a proximity sensor that uses an emitter (e.g., an infrared LEDor a radiation source that operates in another frequency) and a receiveror detector (e.g., an infrared receiver or a radiation detector thatoperates in another frequency) for detecting radiation. The proximitysensor may determine the distance to a nearby object by emittingradiation through the emitter and detecting radiation that has reflectedoff of the object, as an example. With one suitable arrangement, one ormore sensors in device 10 may be located underneath cover 54. Forexample, as shown in FIG. 1 device 10 may include one or more sensorsbeneath cover 54 at the location of outline 52. In general, sensors indevice 10 may be located at any suitable location (e.g., in the inactiveperipheral region of display 16).

With one suitable arrangement, the portions of cover 54 above sensors indevice 10 may be transparent or semi-transparent to radiation (i.e.,visible and/or infrared light). As one example, cover 54 may be formedfrom transparent glass that has an opaque coating that does not extendover the sensors in device 10 and that has an infrared coating that doesextend over the sensors. The infrared coating may have an appearancesimilar to the opaque coating in the visible spectrum (blocking visiblelight) but may be transparent to infrared radiation. With anothersuitable arrangement, the opaque coating over cover 54 may extend oversome or all of the sensors in device 10 and may include a plurality ofmicroperforations. For example, cover 54 may include a black mask (e.g.,a black paint) with a plurality of microperforations. Themicroperforations in the black mask may be located between sensors indevice 10 and the external environment such that radiation can passbetween the sensors and the external environment. With one suitablearrangement, the opaque coating on cover 54 may be formed from a thinlayer of metal deposited onto the glass of cover 54 using a physicalvapor deposition process. The microperforations may be formed by etchingaway selected portions of the deposited metal layer using a laser, usingphotolithographic patterning techniques, etc.

A schematic diagram of an embodiment of an illustrative portableelectronic device such as a handheld electronic device is shown in FIG.2. Portable device 10 may be a mobile telephone, a mobile telephone withmedia player capabilities, a handheld computer, a remote control, a gameplayer, a global positioning system (GPS) device, a laptop computer, atablet computer, an ultraportable computer, a hybrid device thatincludes the functionality of some or all of these devices, or any othersuitable portable electronic device.

As shown in FIG. 2, device 10 may include storage 34. Storage 34 mayinclude one or more different types of storage such as hard disk drivestorage, nonvolatile memory (e.g., flash memory or otherelectrically-programmable-read-only memory), volatile memory (e.g.,battery-based static or dynamic random-access-memory), etc.

Processing circuitry 36 may be used to control the operation of device10. Processing circuitry 36 may be based on a processor such as amicroprocessor and other suitable integrated circuits. With one suitablearrangement, processing circuitry 36 and storage 34 are used to runsoftware on device 10, such as internet browsing applications,voice-over-internet-protocol (VOIP) telephone call applications, emailapplications, media playback applications, navigation functions, mapfunctions, operating system functions, power management functions, etc.

Input-output devices 38 may be used to allow data to be supplied todevice 10 and to allow data to be provided from device 10 to externaldevices. Display screen 16, button 19, microphone port 24, speaker port22, and dock connector port 20 are examples of input-output devices 38.In general, input-output devices 38 may include any suitable componentsfor receiving input and/or providing output from device 10. For example,input-output devices 38 can include user input-output devices 40 such asbuttons, touch screens, cameras, joysticks, click wheels, scrollingwheels, touch pads, key pads, keyboards, microphones, etc. A user cancontrol the operation of device 10 by supplying commands through userinput devices 40.

Input-output device 38 may include sensors 41 such as proximity sensors,ambient light sensors, orientation sensors, proximity sensors, and anyother suitable sensors.

Display and audio devices 42 may include liquid-crystal display (LCD)screens or other screens, light-emitting diodes (LEDs), and othercomponents that present visual information and status data. Display andaudio devices 42 may also include audio equipment such as speakers andother devices for creating sound. Display and audio devices 42 maycontain audio-video interface equipment such as jacks and otherconnectors for external headphones and monitors.

Wireless communications devices 44 may include communications circuitrysuch as radio-frequency (RF) transceiver circuitry formed from one ormore integrated circuits, power amplifier circuitry, passive RFcomponents, antennas, and other circuitry for handling RF wirelesssignals. Wireless signals can also be sent using light (e.g., usinginfrared communications).

Device 10 can communicate with external devices such as accessories 46,computing equipment 48, and wireless network 49, as shown by paths 50and 51. Paths 50 may include wired and wireless paths. Path 51 may be awireless path. Accessories 46 may include headphones (e.g., a wirelesscellular headset or audio headphones) and audio-video equipment (e.g.,wireless speakers, a game controller, or other equipment that receivesand plays audio and video content), a peripheral such as a wirelessprinter or camera, etc.

Computing equipment 48 may be any suitable computer. With one suitablearrangement, computing equipment 48 is a computer that has an associatedwireless access point (router) or an internal or external wireless cardthat establishes a wireless connection with device 10. The computer maybe a server (e.g., an internet server), a local area network computerwith or without internet access, a user's own personal computer, a peerdevice (e.g., another portable electronic device 10), or any othersuitable computing equipment.

Wireless network 49 may include any suitable network equipment, such ascellular telephone base stations, cellular towers, wireless datanetworks, computers associated with wireless networks, etc.

A conventional arrangement for mounting a sensor beneath cover glass ina cellular telephone is shown in FIG. 3. As shown in FIG. 3, cellulartelephone 200 includes cover glass 202. Cover glass 202 includes blackpaint 204 that serves as an opaque backing to cover glass 202. Infraredlight sensor 206 is located underneath the cover glass 202. Black paint204 does not extend between sensor 206 and cover glass 202. Instead,infrared ink 208 is placed between sensor 206 and cover glass 202 toallow infrared radiation to pass between sensor 206 and the externalenvironment. Typically, infrared ink 208 has an appearance that issimilar to black paint 204 in the visible spectrum. Because conventioninfrared ink 208 has a nearly black appearance, it is difficult tomaintain a uniform aesthetic appearance for conventional devices such asdevice 200 when the backing is not black in appearance.

In contrast, device 10 of FIG. 1 may incorporate a cover 54 thatincludes a backing that is not necessarily black in appearance. Ingeneral, the backing to cover 54 may be any suitable color and mayinclude combinations of colors and/or patterns. With one suitablearrangement, the backing to cover 54 may have a silver color and may bemetallic in appearance. In this example, the backing to cover 54 may beformed from using a physical vapor deposition process to depositmetallic material onto cover 54 (e.g., to deposit a thin metal layeronto cover glass 54). The backing to cover 54 may or may not be opaque.Opaque backings may be used to obscure internal components in device 10from a user's view and transparent or semi-transparent backings may beused to showcase some or all of the internal components in device 10, ifdesired. In addition, because the backing to cover 54 may not rely uponinfrared ink to obscure internal components such as sensors, the sensorsin device 10 may be able to effectively transmit and receive radiationin the visible light spectrum.

As shown in FIG. 4, device 10 may include an opaque backing 56 thatextends substantially over an entire surface of cover 54. Backing layer56 may include microperforations (e.g., relatively small holes) inregion 58 in order to allow radiation (e.g., visible light and infraredlight) to pass through the backing 56. With one suitable arrangement,cover 54 may be formed from transparent glass and backing 56 may be anopaque material such as paint, a metallic layer, ink, etc.

In general, microperforations may refer to relatively small holes thatare substantially invisible while still transmitting a certain degree oflight. The microperforations may be essentially invisible to a user butmay allow enough light to pass through. As one example, whenmicroperforations are formed in an opaque material, themicroperforations may be invisible (e.g., the opaque material may have arelatively seamless appearance) unless a light source illuminates themicroperforations (e.g., passes light through the microperforations)from the opposite side of the material. If desired, themicroperforations may be filled with a transparent material such as aclear epoxy material. As one example, the microperforations may beformed with a tapered shape (e.g., the width of the microperforationsmay increase from a minimum width at the outer surface of backing 56(e.g., the surface closest to the exterior environment) to a maximumwidth at the inner surface of backing 56 (e.g., the surface closest tothe interior of device 10). Alternatively, the microperforations mayhave a relatively straight shape (e.g., a uniform diameter throughbacking 56). With one suitable arrangement, each of themicroperforations in device 10 may have a diameter of approximately 30micrometers and the pitch (center-to-center spacing) of themicroperforations may be approximately 200 micrometers. If desired, thepitch of the microperforations may be less than 200 micrometers, greaterthan 200 micrometers, less than 500 micrometers, less than 1 millimeter,etc. As one example, the pitch of the microperforations may be in therange of 100 micrometers to 300 micrometers.

FIGS. 4 and 5 illustrate two ways in which the microperforations inregion 58 of backing 56 may be formed. As one example, microperforationsin region 58 of backing 56 may be formed by selectively removingportions of backing 56 using a laser cutting process. As shown in theFIG. 4 example, lasers may cut microperforations in region 58 of backing56 by directing laser light along direction 60 towards backing 56.Alternatively, as shown in the FIG. 5 example, lasers may cutmicroperforations in region 58 of backing 56 by directing laser lightalong direction 64 through glass cover 54 towards backing 56. Themicroperforations may have, for example, a diameter in the range of 0.05to 1.0 mm. If desired, the microperforations may have a diameter that isless than 0.05 mm.

As shown in FIG. 5, sensors such as sensor 62 may be mounted beneathcover glass 54 in device 10 (e.g., after the microperforations have beenformed). In particular, sensor 62 may be mounted under cover glass 54(e.g., a glass substrate) and region 58 of backing 56 (e.g., amicroperforated region of backing 56). With this type of arrangement,radiation required for the operation of sensor 62 may pass through cover54 and region 58 of backing 56. Sensor 62 may include one or moreemitters and/or detectors that sense attributes of the environmentaround device 10. Sensors 62 may, for example, be an infrared lightsensor or visible light sensor for making ambient light measurements.

If desired, cover 54 may extend substantially across the entire frontface of device 10 (e.g., the face shown in FIG. 1 which includes button19, display 16, and port 23). This type of arrangement may create asmooth surface and may also enhance the aesthetic appearance of device10. Backing 56 may also extend substantially over the front face ofdevice 10. As shown in the example of FIG. 6, cover 54 may have holes inregions 70 and 72 and backing 56 may have holes in regions 68, 70, and72. The holes in cover 54 and backing 56 may allow display 16 to emitlight through cover 54, button 19 to be accessed by a user, and soundand radiation (light) to pass through cover 54 to port 23.

As shown in FIG. 6, device 10 may include sensors 74 (e.g., sensors 62).Sensors 74 may include an emitter and detector pair configured as aproximity sensor and an ambient light sensor, as an example. Sensors 74may be mounted underneath cover 54 and backing 56. As described inconnection with FIGS. 4 and 5, the backing 56 to cover 54 may have aplurality of small holes (microperforations) above each of the sensors74 to allow radiation to pass between the sensors and the externalenvironment.

With one suitable arrangement, microperforations in backing 56 of cover54 may be optimized to maximize the performance of the sensors 74. Withanother suitable arrangement, the microperforations in backing 56 may beoptimized to maximize the aesthetic appearance of device 10 (e.g., tominimize the visibility of the microperforations of a user of device10). The microperforations in backing 56 may be designed to achieve adesired balance between sensor performance and aesthetic appearance. Ingeneral, sensor performance may be increased by increasing the number ofmicroperforations, increasing the size of the microperforations,decreasing the distance between each microperforation, etc. In contrast,aesthetic appearance (e.g., the invisibility of the microperforationsand underlying sensors) may generally be increased by decreasing thenumber of microperforations, decreasing the size of themicroperforations, increasing the distance between eachmicroperforation, etc.

If desired, one or more of the sensors 74 may include a camera. As anexample, sensor 75 may be a camera. If desired, whole portions ofbacking 56 (rather than microperforations) may be removed above sensor75. With one arrangement, the portion of backing 56 inside outline 66may be removed. This type of arrangement may improve the performance ofcamera 75 by increasing the amount of light that reaches the camera 75.

A close-up of the microperforations in backing 56 (e.g., a light maskassociated with cover 54) is shown in FIG. 7. As the example of FIG. 7shows, backing 56 may include a plurality of relatively smallperforations 76 (holes) in which the backing material (e.g., paint,metallic layer, etc.) has been removed. Each of the perforations 76 maybe evenly spaced from other perforations 76 (e.g., the perforations 76may be formed in a pattern or an array). As an example, the perforations76 may have a diameter of approximately 75 microns. If desired, each ofthe perforations 76 may have a diameter that is more than 75 microns ora diameter that is less than 75 microns. In general, the perforations 76may be formed in any suitable shape and may be arranged in any suitablemanner (e.g., in an array, in a pattern, randomly, etc.). Theperforations 76 may allow radiation to pass between sensors and theenvironment. The perforations 76 may be arranged in an array. With onesuitable arrangement, the microperforations 76 may be formed by using alaser to remove the backing material at the location of eachmicroperforation 76 (e.g., by starting with a complete backing layer andcreating microperforations). Alternatively, microperforations 76 may beformed as the backing material is formed on cover 54. For example,backing 56 may be printed onto cover 54 (e.g., using screen printingtechniques) and the microperforations 76 may be formed during theprinting process (e.g., microperforations 76 may be formed by printingbacking 56 onto cover 54 using a pattern that does not print backingmaterial onto the microperforations 76).

As described in connection with FIG. 1, device 10 may include a displaysuch as display 16 that is configured to minimize light leakage. Anexample of a display such as display 16 that includes structures toreduce light leakage is shown in FIG. 8.

As shown in FIG. 8, display 16 may include one or more light sourcessuch as light emitting diodes 82 (e.g., a back light for display 16).Light emitting diodes 82 may be arranged along a top edge of display 16and the light from diodes 82 may be distributed throughout display 16using a light guide. Each of the light emitting diodes 82 may be formedfrom a light emitting diode that produces white light. In general,display 16 may include any suitable light source such as a white lightemitting diode (LED), a combination of red, blue, and green lightemitting diodes, a cold cathode fluorescent lamp (CCFL), an incandescentlight bulb, an electroluminescent panel (ELP), a hot cathode fluorescentlamp (HCFL), other suitable light sources, or a combination of these andother light sources.

Display 16 may include a connection interface 84. Connection interface84 (e.g., a connector) may convey signals between display 16 andcircuitry in device 10 such as processing circuitry 36 and videoprocessing circuitry in device 10. Connection interface 84 may be basedon any suitable type of interface. If desired, connection interface 84may be formed from a flex circuit.

The back face of display 16 (e.g., the face of display 16 opposite theface that displays images for a user) may be substantially covered by areflector 78. If desired, reflector 78 may be replaced with a planarbacking structure rather than a reflecting structure. Reflector 78 mayalso be referred to as a planar backing structure. Reflector 78 maycover a light guide layer 86 in display 16, as one example. Layer 86 maybe located substantially underneath reflector 78 in FIG. 8 and istherefore not shown separately in FIG. 8. Generally, reflector 78 helpsto direct light towards the front face of display 16 and therebyincrease the efficiency of display 16 by redirecting light that wouldotherwise escape through the back face of display 16. At the interfaceof reflector 78 and chassis 94 (e.g., a plastic support structure) oranother portion of display 16, light may escape from display 16 (e.g.,light may exit display 16 not through the desired display face or frontface). This can lead to an unsightly condition in which light that hasescaped from the rear face or sides of display 16 can enter the interiorof device 10 and illuminate cracks or gaps in housing 12 of device 10.

Light leakage can be reduced by providing display 16 with opaque member80. Opaque tape 80 may be, as an example, a double-sided tape (e.g., atape with adhesive on two sides). Opaque tape 80 may help to reduce oreliminate light leakage from display 16 by limiting the amount of lightthat can escape from the gap between reflector panel 78, the underlyinglayers of display 16 such as light guide 86, and chassis 94, as anexample. Tape 80 may cover the gap between panel 78 and chassis 94. Withone suitable arrangement, tape 80 may be formed from a black tape. Ifdesired, tape 80 may be formed from a tape which is white on the sideplaced against panel 78 and chassis 94 and that is black on the oppositeside. As an example, tape 80 may be added to the interior of display 16(e.g., tape 80 applied to an interior surface of chassis 94 and panel78). With this type of arrangement, the light leakage from display 16may be reduced without negatively affecting the white balance of display16.

While tape 80 only extends across two of the edges of reflector 78 inthe FIG. 8 example, in general tape 80 may be formed on any suitableportions of reflector 78. If desired, tape 80 may extend around theentire perimeter of reflector 78.

Display 16 may be formed from a plurality of layers held together in achassis. For example, as shown in FIG. 9, display 16 may include a glasspanel layer 88, a brightness enhancement film (BEF) 90, a diffuser film92, light guide 86, and reflector 78. These layers may be sandwichedtogether and supported by chassis 94 (e.g., a plastic supportstructure). With one suitable arrangement, chassis 94 may be formed froma black material or may be formed from a material that is white on theinward facing sides of chassis 94 and that is black on the outwardfacing sides of chassis 94 (e.g., the exterior surface of chassis 94).This type of arrangement may help to reduce light leakage from display16.

Light guide 86 may be coupled to light source 82 (shown in FIG. 8) ofdisplay 16. Light guide 86 may serve to evenly distribute the light fromlight source 82 across display 16.

As discussed in connection with FIG. 8, reflector 78 may redirect anylight that is heading away from the desired direction for display 16.For example, it is desirable for light to be emitted by display 16 alongdirection 96. Reflector 78 may therefore redirect light that is headedin the direction 97 so that the redirected light is heading in thedirection 96.

Diffuser film 92 may even out the light distributed by light guide 86.As an example, the light distributed by light guide 86 may be somewhatmore intense (e.g., brighter) near light source 82 and somewhat lessintense away from light source 82. Diffuser film 92 may help to counterthe uneven intensity of light distributed by light guide 86 by diffusinglight away from the higher intensity regions (near light source 82)towards the lower intensity regions (at the far end of display 16opposite light source 82).

Brightness enhancement film 90 may enhance the brightness of display 16.With one suitable arrangement, film 90 may have a prismatic structure(or other suitable structure) and may refract light along direction 96,if the light hits the prismatic structure at a particular angle, and mayreflect the rest of the light (e.g., via an total internal reflection)back towards reflector 78 (e.g., along direction 97). If desired, film90 may be a multi-layer optical film. With another suitable arrangement,film 90 may be used to increase the brightness of display 16 by managingthe polarization of light that enters glass panel 88. Because glasspanel 88 may include one or more polarizers, managing the polarizationof light using film 90 can increase the efficiency and brightness ofdisplay 16. With this type of arrangement, film 90 may selectively passa light in a particular polarization to panel 88 (e.g., a polarizationthat may be aligned with a polarizer in panel 88) while reflecting otherpolarizations back towards reflector 86 (e.g., along direction 97).Because the light received by glass panel 88 is already in the correctpolarization (in this example) less light may be absorbed by a polarizerin panel 88 and the overall amount of light emitted by display 16 alongdirection 96 may be increased.

Glass panel 88 may include an LCD panel. A cross-sectional view of glasspanel 88 is shown in FIG. 10. As an example, glass panel 88 may includebottom polarizer 98, array glass 100, thin film transistor and liquidcrystal layer 102, color filter glass 104, and top polarizer 106.

With one suitable arrangement, light from light sources 82 may enterglass panel 88 along direction 108 and pass through polarizer 98.Polarizer 98 may ensure that the light entering glass panel 88 shares acommon polarization.

After the light has passed through polarizer 98 and been polarized, thepolarized light may pass through array glass 100. Array glass 100 may bea substrate layer on which thin-film-transistors may be formed. Thepolarized light may then pass through thin film transistor and liquidcrystal layer 102. Layer 102 may include an array of liquid crystalseach of which is controlled by a respective thin film transistor. As thepolarized light passes through layer 102, the liquid crystals in layer102 may be used to selectively alter the polarization of the light. Theamount by which a given liquid crystal changes the polarization of lightpassing through it will typically depend on control signals receivedfrom the thin film transistor associated with the liquid crystal.

Color filter glass 104 may selectively filter the light received fromlayer 102 into an appropriate color. For example, each pixel in display16 may be formed from three sub-pixels. Each sub-pixel may be formedfrom a single liquid crystal and may be used to produce one of the threeprimary colors red, blue, or green. Color filter glass 104 may then beused to filter the light coming from each sub-pixel into the appropriateprimary color (e.g., filter glass 104 may be an array designed to turnthe light from each red sub pixel into red light, the light from eachblue sub pixel into blue light, and the light from each green sub pixelinto green light).

Polarizer 106 may then filter the light before it leaves glass panellayer 88. With one arrangement, polarizer 106 may be configured to passlight with a polarization that is ninety degrees from the polarizationof light from polarizer 98. With this arrangement, the amount to whichliquid crystals in layer 102 change the polarization of light passingthrough layer 102 will determine the brightness of each individual pixelin display 16.

FIG. 11 illustrates how display 16 may be mounted to a mountingstructure in device 10. As shown in FIG. 11, display 16 may be mountedto a mounting structure 110 in device 10 using tape 80. Tape 80 may be adouble-side tape that also helps to prevent light leakage from display16. With another suitable arrangement, display 16 may be mounted tomounting structure 110 using adhesive. Mounting structure 110 may be aportion of housing 12 or, if desired, may be a structure in device 10sometimes referred to as a midplane (e.g., an internal metal structurein device 10 that can be used as a mounting point for various internalcomponents such as display 16, storage devices, processing circuitry,etc.).

A conventional display module 210 is shown in FIG. 12. Display module210 includes reflector 212, glass layer 214, chassis 216, and clear tape218. Clear tape 218 serves to hold reflector 212 and layer 214 togetherand also holds reflector 212 and layer 214 to chassis 216. However, asshown in FIG. 12, light can escape from glass layer 214 and enter cleartape 218 as indicated by the arrow 220. Once light has entered cleartape 218, the light can leak from display module 210.

In contrast, opaque tape 80 can help to reduce or eliminate leak leakagefrom display 16 of FIG. 1 by limiting the amount of light that canescape from display 16. A close up view of the rear of display 16 isshown in FIG. 13 which illustrates how opaque tape 80 helps to preventlight from escaping from display 16. As shown in FIG. 13, opaque tape 80may overlap a gap 81 between reflector layer 78 and light guide 86. Tape80 may also hold reflector layer 78 and light guide 86 to chassis 94, ifdesired. Because tape 80 is formed from an opaque material such as anopaque polymer, tape 80 will help to prevent light leakage from any gaps(e.g., gaps 81) between reflector 78 and light guide 86 in display 16.

If desired, tape 80 may be formed from a transparent material. With thistype of arrangement, an opaque material may be applied to the exteriorof tape 80 to reduce light leakage. For example, a black paint may beapplied to the exterior of a clear version of tape 80 to effectivelymake tape 80 opaque.

If desired, device 10 of FIG. 1 may include a compression spring thatcan be fully compressed without deforming. The compression spring may bepart of a resilient button mechanism, as one example. In general, device10 may include one or more compression springs. The compression springsmay sometimes be referred to as variable cantilever compression springs.FIG. 14 illustrates one potential variable cantilever compression spring114 that could be a part of device 10. Spring 114 may be formed from asingle piece of metal with an elongated flat section 116, first curvedportion 118, second curved portion 124, and contact member 126, as anexample. Portions 124 and 116 may sometimes be referred to as curvedstructure 124 and elongated planar structure 116. Curved structure 124may be coupled to elongated planar structure 116 at one of the ends ofcurved structure 124. First curved portion 118 may include two bends 120and 122. With another suitable arrangement, curved section 124 may bedirectly connected to section 116 (e.g., curved section 118 may beremoved). Portion 124 may have a relatively constant upward curvatureover the majority of its length. If desired, spring 114 may beconfigured so that bends 120 and 122 in section 118 undergosubstantially no elastic or plastic deformation when spring 114 iscompressed.

With one suitable arrangement, spring 114 may be referred to as avariable cantilever spring because of its dynamic response to increasingcompression. For example, the length of the cantilever of spring 114(e.g., curved portion 124) may dynamically decrease as spring 114 iscompressed. The length of the cantilever of spring 114 may be thedistance between the contact region 126 and the closest point of contactbetween curved member 124 and structure 116. In this configuration, whenspring 114 is relatively uncompressed, the length of the cantilever willessentially be the full length of member 124 and, when spring 1214 ispartially compressed, the length of the cantilever will be reducedrelative to the full length of member 124, thereby stiffening spring 114as the spring is compressed. The length of the cantilever may be reduceby an amount proportional to the amount spring 114 is compressed. Incontrast, the length of the cantilever of a conventional cantileveredspring is constant and does not change as the conventional spring iscompressed.

Spring 114 may be relatively resistant to fatigue. As an example, thecurved portion 118 of spring 114 typically experiences relatively highstress levels during the manufacture of spring 114 (e.g., because curvedportion 118 may include the sharpest bends in spring 114) andexperiences relatively low stress levels during normal use (e.g.,compression and release of spring 114). In contrast, curved portion 124typically experiences relatively low stress levels during manufacturingand experiences relatively high stress levels during normal use. Thistype of arrangement may increase the resistance of spring 114 to metalfatigue relative to conventional spring designs in which the sharpestbends are prone to breakage.

With one suitable arrangement, the elongated section 116 of spring 114may be used as a first contact or attachment point to connect or attachspring 114 to a desired structure in device 10. Contact member 126 maybe used a second contact or attachment point to connect or attach spring114 to a desired structure in device 10. As spring 114 is compressed,contact member 126 may be depressed towards section 116 of spring 114.The point of contact between sections 116 and 124 of spring 114 maycontinually shift (e.g., progressively curve away from section 118) asspring 114 is compressed. For example, when spring 114 is in its naturalstate (e.g., no force is pressing member 126 towards section 116), thepoint of contact between sections 116 and 124 may be in region 122 ofcurved portion 124. As spring 114 is compressed, the point of contactbetween sections 116 and 124 may shift from section 118 towards member126. The point of contact may shift continuously as spring 114 iscompressed or may shift incrementally as spring 114 is compressed (e.g.,curved section 124 may be formed from a plurality of straight sectionswith bends between them while maintaining the overall shape of thesection 124 shown in FIG. 14). When spring 114 is completely compressed(e.g., member 126 is pressed directly against section 116), section 124may lie relatively flat against 116. The arrangement of FIG. 14 helps toensure that spring 114 does not undergo plastic deformation even whenspring 114 is completely compressed.

A side view of spring 114 is shown in FIG. 15. As shown in FIG. 15,spring 114 may have an uncompressed height of approximately 1.85 mm asindicated by arrows 130 (e.g., spring 114 may have an uncompressedheight in the range of 1.50 mm to 2.00 mm). Contact member 126 may havea thickness of approximately 0.19 mm as indicated by arrows 128 (e.g., athickness in the range of 0.1 mm to 0.5 mm). As one example, curve 124may have a bend radius of approximately 2.75 mm when spring 114 isuncompressed (e.g., a bend radius in the range of 2.0 mm to 3.5 mm).Curved portion 118 may have a thickness of approximately 0.32 mm asindicated by arrows 134 (e.g., a thickness in the range of 0.1 mm to 0.5mm). The second bend 122 of curved portion 118 may contact section 116or, if desired, may be separated from section 116 by a gap ofapproximately 0.20 mm as indicated by arrows 132 (e.g., a gap in therange of 0.01 mm or less to 0.5 mm). Section 124 may have anuncompressed length (from curved portion 120 to contact member 126) ofapproximately 3.48 mm as indicated by arrows 158 (e.g., a length in therange of 2.5 mm to 5.0 mm).

A bottom view of the variable cantilever spring 114 is shown in FIG. 16.As FIG. 16 illustrates, section 116 of spring 114 may include a contactpatch 140 and a floating patch 142. The floating patch 142 of spring 114may extend approximately 1.5 mm as indicated by arrows 136 from curvedportion 118 towards contact patch 140. With one suitable arrangement,floating patch 142 may not be mounted to any other structure (e.g.,patch 142 may freely flex as spring 114 is compressed). With this typeof arrangement, spring 114 may be mounted in device 10 by securingcontact patch 140 of spring 114 to a suitable mounting structure. As oneexample, patch 140 may be soldered to a mounting structure in device 10.In general, any suitable portion of spring 114 such as patch 140 orpatch 142 (if desired) may be mounted to a structure in device 10 usingany suitable means such as an adhesive, a tape, a mechanical fastener,by soldering, by another suitable means, or by a combination of theseand other means.

A top view of spring 114 is shown in FIG. 17. As shown in FIG. 17,contact portion 126 of spring 114 may include a contact area that isapproximately 1.00 mm in length as indicated by arrows 148. With onesuitable arrangement, contact portion 126 of spring 114 may extendacross the shaded region of FIG. 17. With one suitable arrangement,spring 114 may have a width in the range of approximately 0.7 to 0.9 mmas illustrated by arrows 146 and may have a length of approximately 4.65mm as illustrated by arrows 144.

Spring 114 may be formed from any suitable elastic material such as aspring metal. For example, spring 114 may be formed from steel, bronze,titanium, copper, other suitable elastic materials, or a combination ofthese and other suitable materials. With one suitable arrangement,spring 114 may be formed from a beryllium copper alloy with a thicknessof approximately 0.08 mm and with a Vickers Pyramid Number (HV) in therange of approximately 300-340. If desired, spring 114 may be plated(e.g., to reduce contact resistance). As an example, some or the entiresurface of spring 114 may be plated with gold (or other suitablematerial). With one suitable arrangement, contact portion 126 (e.g., theshaded region in FIG. 17) may be plated with gold with a platingthickness in the range of approximately 0.3 micrometers to 0.45micrometers. Spring 114 may also include nickel plating between the goldplating and spring 114. For example, spring 114 may include a nickelplating sometimes referred to as a barrier layer with a thickness in therange of 1.0 to 1.5 micrometers. If desired, the nickel plating orbarrier layer may extend over the entire surface of spring 114. Ingeneral, spring 114 may include any suitable combination of platings andbarrier layers formed from any suitable materials. With one suitablearrangement, spring 114 may have a contact resistance (e.g., aresistance between an external member and spring 114 through contactregion 126) of approximately 0.005 ohms with a contact force ofapproximately 0.3 newtons (N).

If desired, spring 114 may include a structure which increases theuncompressed height of the spring following a nearly complete orcomplete compression of spring 114. For example, as shown in FIG. 18,the tip of spring 114 (e.g., the portion of spring 114 near contactpatch 126) may be curved back towards the base of spring 114 (e.g.,section 116 of spring 114) as illustrated by solid line 153 of FIG. 18.If spring 114 is compressed sufficiently (e.g., spring 114 is compressedto the position indicated by the dotted line 150), the tip of spring 114may be bent away from the base of spring 114 (e.g., the tip of spring114 may undergo plastic deformation). After the tip of spring 114 isbent away from the base of spring 114, the tip may rest in the positionof dotted line 152 when the spring is uncompressed. This type ofarrangement may be useful in increasing the uncompressed height of thespring following a relatively large compression. The resiliency ofspring 114 may therefore be increased as a complete compression ofspring 114 increases the distance that the spring 114 can be compressed.

If desired, spring 114 may be used to stiffen a mounting structure.Section 140 of spring 114 may be used to stiffen a mounting structuresuch as mounting structure 156. Mounting structure 156 may include anysuitable structure such as a printed circuit board and a flex circuit.With this type of arrangement, a component 154 may be mounted tomounting structure 156 opposite spring 114. By utilizing spring 114 as astiffener of mounting structure 156, component 154 may be mounted to amore flexible mounting structure 156 than would otherwise be practical(e.g., without having to add an addition stiffening structure, therebyreducing the number of components required). Component 154 may includeany suitable component such as a flex circuit connector, processingcircuitry, storage, input-output circuitry, etc.

Device 10 may include one or more springs 114 as part of a buttonmechanism. As one example, device 10 may include two springs 114 thatconvey signals from a button such as button 19 between a pair of flexcircuits as shown in FIG. 19. While the example of FIG. 19 shows the twosprings 114 arranged at different distances from button 19, springs 114may be arranged side-by-side (i.e., at similar distances from button19), if desired.

The physical button 19 on the exterior surface of device 10 may becoupled to a switch mechanism 160 and a circuit board 162, as anexample. Circuit 162 may be any suitable type of circuit such as a flexcircuit or a printed circuit board. Switch mechanism 160 may be based ona dome switch mechanism or any other suitable button mechanism. With adome switch mechanism, the dome of mechanism 160 will collapse whenbutton 19 is pressed by a user. When the dome of mechanism 160 collapsesit completes a circuit between two conductive lines. With one suitablearrangement, each of the two springs 114 in FIG. 19 may be coupled to arespective one of the two conductive lines through flex circuit 162.Each of the two springs 114 may also be coupled to a respectiveconductive line that is coupled to circuitry 172 through circuit 166 andcontact patch 168. With this type of arrangement, when button 19 ispressed by a user and the dome switch mechanism 160 completes thecircuit between the two conductive lines, a conductive loop may beformed that begins at circuitry 172, that passes through the two springs114 and button mechanism 160, and ends at circuitry 172.

Contact patch 140 may be coupled to flex circuit 162. If desired, thecontact patch 126 of each spring 114 may bear against contact region 168of flex circuit 166. With one suitable arrangement, as one of thesprings 114 is compressed, the contact patch 126 of the spring may slidealong contact region 168 of circuit 166. Contact region 168 may beplated with a suitable material. As an example, contact region 168 offlex circuit 166 may be plated with gold.

Circuit 166 may be any suitable type of circuit such as a flex circuitor a printed circuit board and may be mounted on structure 170, as anexample. Structure 170 may be a speaker enclosure or other suitablestructure.

The foregoing is merely illustrative of the principles of this inventionand various modifications can be made by those skilled in the artwithout departing from the scope and spirit of the invention.

What is claimed is:
 1. An electronic device comprising: a transparentcover; a mask covering a portion of the transparent cover, wherein themask comprises portions defining a plurality of holes; a given sensormounted beneath the transparent cover and the plurality of holes in themask; and a touchscreen display having touch sensors in an active regionof the touchscreen display, wherein the given sensor is located in aninactive region of the touchscreen display, wherein the portionsdefining the plurality of holes in the mask are configured to allowlight for the given sensor to pass through the holes in the mask whileobscuring the given sensor from view, and wherein the transparent coverextends over the inactive region of the touchscreen display.
 2. Theelectronic device defined in claim 1 wherein each of the plurality ofholes has a center and is adjacent to at least one other hole in theplurality of holes and wherein the centers of adjacent holes areseparated by a distance in the range of 100 micrometers to 300micrometers.
 3. The electronic device defined in claim 1 wherein thegiven sensor comprises an ambient light sensor that measures visiblelight that is received through the holes.
 4. The electronic devicedefined in claim 1 wherein the given sensor comprises a proximitydetector that detects the presence of an object when the object comeswithin a given distance of the electronic device.
 5. The electronicdevice defined in claim 1 wherein the given sensor comprises an emitterand a receiver pair configured as a proximity detector and wherein themask comprises portions defining a plurality of additional holes, theelectronic device further comprising: an ambient light sensor mountedbeneath the transparent cover under the plurality of additional holes inthe mask.
 6. The electronic device defined in claim 1 wherein the maskcomprises a metallic layer.
 7. The electronic device defined in claim 1wherein the mask comprises ink.
 8. The electronic device defined inclaim 1 further comprising: a button that receives user input, whereinthe transparent cover and the mask comprise portions defining a buttonhole and wherein the button extends at least partway into the buttonhole; and a spring coupled to the button, wherein the spring has anelongated planar structure and has a curved structure coupled to theelongated planar structure at a given end of the curved structure,wherein the curved structure progressively curves away from theelongated planar structure along its length, wherein the curvedstructure is configured to provide resistance to a force compressing thecurved structure towards the elongated planar structure, and whereinthere is a point of contact between the curved structure and theelongated planar structure that shifts away from the given end of thecurved structure as the curved structure is compressed towards theelongated planar structure.
 9. The electronic device defined in claim 1,wherein the transparent cover extends over the touchscreen display. 10.An electronic device, comprising: a display having a transparent coverwith an active image area and an inactive peripheral region; a lightsensor under the inactive peripheral region; and an opaque layer on thetransparent cover in the inactive peripheral region, wherein the opaquelayer comprises an array of holes through which light passes to thelight sensor while the opaque layer obscures the light sensor from view.11. The electronic device defined in claim 10 wherein the transparentcover comprises a glass cover and wherein the display comprises a touchscreen display.
 12. The electronic device defined in claim 10 whereinthe opaque layer comprises a layer of metal.
 13. The electronic devicedefined in claim 10 wherein the opaque layer comprises a layer of metaland wherein the holes each have a diameter of less than 0.5 mm.
 14. Theelectronic device defined in claim 10 wherein each of the holes has acenter and is adjacent to at least one other hole in the array of holesand wherein the centers of adjacent holes are separated by a distance inthe range of 100 micrometers to 300 micrometers.
 15. The electronicdevice defined in claim 10 wherein the light sensor comprises an ambientlight sensor that measures visible light that is received through theholes.
 16. The electronic device defined in claim 10 wherein the lightsensor comprises a proximity detector that detects the presence of anobject when the object comes within a given distance of the electronicdevice.
 17. The electronic device defined in claim 10 wherein the lightsensor comprises an ambient light sensor and wherein the opaque layercomprises portions defining a plurality of additional holes, theelectronic device further comprising: an emitter and receiver pairconfigured as a proximity detector, wherein the emitter and receiverpair are mounted beneath the transparent cover under the plurality ofadditional holes in the mask.
 18. The electronic device defined in claim10 wherein the opaque layer comprises ink.
 19. The electronic devicedefined in claim 10 further comprising: a button that receives userinput, wherein the transparent cover and the opaque layer compriseportions defining a button hole and wherein the button extends at leastpartway into the button hole; and a spring coupled to the button,wherein the spring has an elongated planar structure and has a curvedstructure coupled to the elongated planar structure at a given end ofthe curved structure, wherein the curved structure progressively curvesaway from the elongated planar structure along its length, wherein thecurved structure is configured to provide resistance to a forcecompressing the curved structure towards the elongated planar structure,and wherein there is a point of contact between the curved structure andthe elongated planar structure that shifts away from the given end ofthe curved structure as the curved structure is compressed towards theelongated planar structure.
 20. The electronic device defined in claim10 wherein the display comprises: a light source; a planar backingstructure; a chassis that holds the light source and the planar backingstructure; and an opaque seal that overlaps a gap between the chassisand the planar backing structure.
 21. An electronic device, comprising:a front surface; a display on the front surface of the electronicdevice; a transparent cover on the front surface of the electronicdevice, wherein the transparent cover extends over an inactive region ofthe display; an opaque layer on the front surface of the electronicdevice and on the transparent cover; and a sensor underneath the opaquelayer, wherein the opaque layer comprises a plurality of holes throughwhich radiation passes and wherein the plurality of holes are alignedwith the sensor, wherein the sensor comprises an emitter and a receiverpair configured as a proximity detector, and wherein the plurality ofholes in the opaque layer are configured to allow radiation for thesensor to pass through the holes in the opaque layer while obscuring thesensor from view.
 22. The electronic device defined in claim 21 whereineach of the holes has a center and is adjacent to at least one otherhole in the array of holes and wherein the centers of adjacent holes areseparated by a distance in the range of 100 micrometers to 300micrometers.
 23. The electronic device defined in claim 21 wherein thedisplay has an active image area and wherein the opaque layersubstantially surrounds the active image area of the display.